1. Field of the Invention
The present invention relates to a mobile communication system, and more particularly, to a method for transmitting messages on a paging channel, in which data burst messages are efficiently transmitted through the paging channel.
2. Discussion of the Related Art
Generally, messages containing short data transmitted through a paging channel are called data burst messages. Also, messages transmitted together with the data burst messages and containing system information and prior information of data transmitted through the paging channel are called overhead messages.
To acquire a system and receive services, a terminal unit should receive all the overhead messages to recognize information of a corresponding system. Accordingly, in case where the data burst messages and the overhead messages should be transmitted on one slot, the overhead messages having higher priority order are first transmitted and the data burst messages are then transmitted. Thus, the terminal unit periodically receives the overhead messages to acquire latest system information and services.
A related art IS-95A system includes five types of overhead messages to be transmitted. To transmit the five overhead messages at least once for 1.28 seconds (16 slots), a transmission interval of the overhead messages is sufficient for 3 slots. Therefore, the paging channel has small transmission load of the overhead messages and delay of the data burst messages rarely occurs.
However, a CDMA 2000 1X system includes eight types of overhead messages to be transmitted, unlike the related art IS-95A system. Accordingly, the CDMA 2000 1X system requires a transmission interval of the overhead messages by 2 slots to transmit all the overhead messages for 1.28 seconds (16 slots). Also, with longer overhead messages due to additional parameters and increasing data burst messages, overload of the paging channel has occurred.
Thus, the data burst messages and the overhead messages are often transmitted on one slot. In this case, a problem arises in that a receiving rate of the data burst messages is reduced.
Also, since the data burst messages are occupied on the paging channel in a large extent, such a problem affects system performance.